1. Field of the Invention
The present invention relates to an ink jet recording head provided with a filter.
2. Description of the Related Art
In recent years, an ink jet recording device and an ink jet printer have been required to provide performance for ensuring high-speed printing and high-image-quality printing. As methods for satisfying such a demand, there have been known a method to increase the number of nozzles and a method for reducing the size of an ink droplet.
Methods for reducing the size of an ink droplet are typically represented by a method for reducing the sizes of discharge ports. In this case, the sizes of the discharge ports are reduced to approximately a few micrometers. In a manufacturing process, however, there are cases where foreign substances, such as wastes, accidentally enter into nozzles, or foreign substances that move together with ink reach the discharge ports. If the sizes of such foreign substances are smaller than the sizes of the discharge ports, then the foreign substances can be discharged out of an ink jet recording head when ink is discharged or the ink jet recording head is initialized or during a recovery sequence. If, however, the sizes of the foreign substances are larger than the sizes of the discharge ports, then the foreign substances will clog the discharge ports or ink flow paths. This prevents the specified discharge performance of the ink jet recording head from being exhibited, resulting in deteriorated yield with a consequent increase in cost.
As a solution to the aforesaid problem, it has been known to provide an ink jet recording head with a filter. For example, U.S. Pat. No. 6,264,309 and Japanese Patent Application Laid-Open No. 2005-178364 have proposed a construction in which a membrane type filter is disposed in an upstream portion of an ink flow path.